Cartridge guide for an automatic gun



Oct. 4, 1966 c. M. CHRISTIANSSON 3,

CARTRIDGE GUIDE FOR AN AUTOMATIC GUN Filed Nov. 24, 1964 2 Sheets-Sheetl FIG. 2

INVENTOR.

CARL MAUR/TZ CHRIST/ANSSON BY I W Oct. 4, 1966 c. M. CHRISTIANSSON3,275,322

CARTRIDGE GUIDE FOR AN AUTOMATIC GUN 2 Sheets-Sheet 2 Filed NOV. 24,1964 INVENTOR. CA R1. NZAUR/TZ CHR/ ST/ANS SON BY M M ATTORNEY:

United States Patent f 3,276,322 CARTRIDGE GUIDE FOR AN AUTOMATIC GUNCarl Mauritz Christiansson, Bofors, Sweden, assignor to AktienbolagetBofors, Bofors, Sweden, a corporation of Sweden Filed Nov. 24, 1964,Ser. No. 413,572 Claims priority, application Sweden, Nov. 26, 1963,13,078/63 4 Claims. '(Cl. 89-33) The invention relates to a device forguiding cartridges in an apparatus for ramming cartridges into thecartridge chamber of an automatic gun, and more'particularly to a deviceof this kind comprising a cartridge-guide in which the cartridgeoccupies a position essentially co-axial with the barrel bore and towhich the cartridge is brought from a cartridge magazine of the gunbefore ramming.

Due to the fact that the bottom part of a cartridgecase comprises aflange which has a somewhat larger diameter than the cartridge-casejacket, it is necessary that the cartridge-guide as well as the breechring and the breech block of the gun, which are located between thecartridge chamber and the cartridge-guide, comprise longitudinallyextending guide means so arranged that they together define a guidesurface having at least as large an internal diameter as the externaldiameter of the flange of the cartridge-case bottom, so as to leave theflange free to pass the cartridge-guide, the breech ring and the breechblock when the cartridge is rammed.

Further, and due to the fact that the case bottom-flange of thecartridge has a larger diameter than the case jacket, and the jacket, inits turn, has a larger diameter than the projectile, which is held in atapering neck of the cartridge-case, the cartridge will rest in thecartridge-guide in a position, in which the axis of the cartridge isdirected obliquely forward-downward as seen from the cartridgecasebottom, and is thus not located so as to be accurately co-axial with thebarrel bore. Such an inclined position of the cartridge relative to thebarrel may cause difficulties in connection with the ramming unlessprovisions are made to prevent such slant of the cartridge duringramming. In particular with the fast ramming movements as are used inrapidly firing guns, dangerous inertia forces and other diflicultiesarise, restricting the loading speed. This is due to the fact that thecartridge-chamber has a smaller diameter than the guide surfaces of thecartridge guide, the breech ring and the breech block which aredimensioned with respect to the diameter of the bottomflange of thecartridge. For this reason, the front part of the cartridge may strikeagainst the rearward edge of the cartridge-chamber and be blocked, or atleast be exposed to a hard lateral shock when pushed into the cor rectposition in the cartridge-chamber.

One object of the invention is to provide a ramming mechanism in whichthe aforementioned disadvantages are essentially eliminated. With thisobject in view the invention relates to a cartridge guide device,comprising a guide means arranged to lift the front part of thecartridge during the movement of the cartridge into thecartridgechamber, so that the cartridge occupies a position essentiallyco-axial with the cartridge-chamber during ramming thereby making itpossible for the cartridge to run into the chamber without the frontpart thereof striking against the rear edge of the chamber, or beingotherwise exposed to interfering powerful lateral forces.

The invention thus relates to a cartridge guiding device of the kindcomprising a cartridge-guide having internal surfaces for guiding acartridge during ramming which together define an at leastpart-cylindric guide means located rearward of and being coaxial withthe cartridge chamber of the gun barrel. The guiding device furthercomprises at least one guide member, which is 3,276,322 Patented Oct. 4,1966 carried by a pivot located below said guide surface and is pivotalabout said pivot between a front position in which an end of said guidemember extends into said cartridge-guide internally of the guidingsurfaces thereof and a rear position in which the guide member islocated externally of said guide surface. The device further com prisesdirectional force means arranged to swing said pivotal guide member intosaid front position and against the action of which the member ispivotal into its rear position. Preferably, the distance over which theguide member extends into the cartridge-guide internally of the guidesurface thereof in its front position equals the difference between thelargest radius of the bottom flange of the cartridge-case and a radiusof the jacket part of the cartridge-case. The cartridge, when lifted bythe guide means during ramming of the cartridge, will then be liftedinto a position substantially co-axial with the axis of thecartridge-chamber of the barrel whereby the cartridge can be rammedwithout parts of the projectile or the neck of the cartridge-case beingexposed to lateral shocks during ramming.

The fact that the rear part of the cartridge is pushed upwardly adistance by the pivotal guide member when the flange of the cartridgepasses the guide member during ramming, does not cause inconvenience. Atthis moment, the front part of the cartridge has already entered so farinto the barrel that it is smoothly guided by the internal surfaces ofthe cartridge-chamber in the barrel.

Due to the fact that a guide member according to the invention isarranged pivotal rearwardly out of the way of the flange of a rearwardlyejected cartridge-case, the ejection may proceed without interference,provided, of course, that the mass of each pivotal guide member and thedirectional force acting thereon are selected in such a manner that theexerted lateral force and thus the acceleration of the cartridge-case ina direction perpendicular to the axis of the cartridge guide by thecartridgecase striking against the guide member are sufliciently small.

In a preferred embodiment of a cartridge-guide the guide surfaces, whichtogether constitute the cartridgeguide, are so arranged that thecartridge is guided around its periphery, the guide surfaces thustogether defining a complete, generally cylindrical guide means, whichhas an internal diameter corresponding to the external diameter of thebottom-flange of the cartridge. With such a cartridge-guide, a guidemember according to the invention, which normally is in its frontposition in which it protrude-s internally of the generally cylindricalguide means, may constitute an obstacle for the bottom flange of thecartridge during ramming. To avoid this, the generally cylindrical guidemeans at such part thereof in its "longitudinal direction at which theguide member in its front position extends inwardly of the cylindricalguide surfaces, is widened upwardly a distance at least equalling thedistance by which the guide member extends upwardly of the cylindricguide surfaces. The guide means thus comprise a bulging surfaceextending upwardly of the major part of the generally cylindric guidesurfaces and the bottom-flange of the cartridge can move past the guidemember or members during ramming without getting blocked.

The invention will become more fully apparent from the followingdescription of a preferred embodiment as illustrated in the accompanyingdrawings, in which:

FIG. 1 is a longitudinal vertical sectional view of the rear part of agun barrel, the breech ring and breech block of the gun, and of acartridge-guide according to the invention, the figure showing acartridge at a moment of its motion through the cartridge-guide duringramming and before the front part of the cartridge has moved upwardsunder the influence of a guide member;

FIG. 2 is a similar sectional view showing the cartridge in a positionin which it has ben aligned with the cartridgeohamber of the barrelduring ramming;

FIG. 3 shows the same details during ejection of a cartridge-casethrough the cartridge-guide after firing; and

FIG. 4 is .a perspective View illustrating an embodiment of acartridge-guide according to the invention more in detail.

FIGS. 1 to 3 show a gun barrel 1 having a cartridgechamber 2 and abreech 'ring 3. A cartridge guide, generally designated 4, is arrangedrearwardly of the breech ring 3 and in alignment with an opening 5 inthe breech ring, through which opening each cartridge is to be rammedinto the cartridge-chamber 2. During ramming a cartridge 7 moves pastand above a breech block 6 into a final position in thecartridge-chamber in which the bottom-flange 8 of the cartridge-caseabuts against the rear edge of the cartridge-chamber. In this positionof the cartridge the breech block 6 can be pushed into a position behindthe cartridge-case bottom before firing.

The diameter of the cartridge bottom flange 8 represents the largestdiameter of the cartridge, and the cartridge tapers successively fromthe bottom to the top thereof, the diameter of the projectile 9 beingmuch smaller than the bottom flange diameter. Consequently, thecartridge occupies a position in the cartridge guide which is somewhatoblique relative to an axis common to the barrel bore, thecartridgescham-ber of the barrel and the cartridge guide. To bring thecartridge into a position, which is substantially co-axial with thecartridge-chamber, the guiding device comprises, according to theinvention, at least one guide member, which in the embodimentschematically illustrated in FIGS. 1 to 3 is represented by a guide lug10 carried by an arm 13. The arm is pivotal about a pivot 12 locatedbelow and outside a guiding surface 11 of the guide 4. By means of adirectional force, as illustrated represented by a spring 16 actuating alever 17 fastened to arm 13, the guide member is normally held in afront or forward position, FIGS. 1 and 2, in which it is swung upwardlythrough an aperture 14 against an abutment member 15. In this frontposition guide lug 10 protrudes above the guide surface 11 a distancewhich preferably substantially corresponds to the difference between theradius of the cartridge-flange 8 and the radius of the substantiallycylindric outer jacket surface 18 of the cartridge.

In FIG. 1, the cartridge 7 is illustrated in a position, in which itrests on the guiding surface 11 of the guide 4 with the edge of itsflange 8 and the front portion of the cylindric surface 18 of thejacket, that is, the cartridge is in a position before it commences toslide upward-s over guide lug 10 with its tapering neck 19.

Assuming that no guiding means corresponding to guide lug '10 werepresent; the cartridge, when moving further forward during the ramming,would then hit the rear edge 20 of the aperture of the cartridge-chamber2, the guide surfaces 21 and 22 of breech block 6 and breech ring 3,respectively, being in alignment with the guiding surfac 11 of thecartridge-guide and thus located below the lower edge of thecartridge-chamber a distance, which corresponds to the distance by whichthe bottom-flange 8 extends externally of the cartridge-jacket adjacentthe bottom-flange.

Due to the provision of the guide member comprising guide lug 10 and arm13 the cartridge will, when moving forward from the position illustratedin FIG. I, slide upwardly over lug 10 and thus be pushed into alignmentwith the axis of cartridge-chamber 2. Accordingly, the cartridge canmove forward into the cartridge-chamber (without the projectile or thefront part of the cartridgecase neck 19 striking against the rear edge20 of the cartridge-chamber or the internal walls of this chamber.

During the forward movement of the cartridge during ramming, the flange8 must also pass past the guide lug 10. To make this possible, thecartridge-guide comprises a widened portion in the form of a bulge 23 onthe upward side thereof. This bulge 23 has a shape such that flange 8,when .sliding upwards via lug 10, can pass freely through the guide 4including the part thereof, where the rear portion of the cartridge islifted by the guide member 10', 13 during ramming.

When the cartridge has been fired and the cartridgecase is ejectedbackwardly from the cartridge-chamber, the velocity of thecartridge-case is so high, that a failure may occur if the bottom-flangeof the case would be forced to move along a stationary or fixed guidemember having a shape such as the guide lug 10. By arranging the guiedlug on a pivotal arm as illustrated, the guide lug can swing backwardlyout of the way of the flange against action of spring 16, as it isindicated in FIG. 3, so that the cartridge case, when ejected, can movealong an essentially linear path.

FIG. 4 illustrates more in detail an embodiment of a cartridge-guideaccording to the invention. In this embodiment, the cartridge-guide hasan upper part comprising two guide bars 31 fastened to the breech ring 3of the gun by means of a flange 30, a longitudinal opening 32 beingprovided to receive a ramming member, not illustrated in the drawings,which is movable within the opening while bringing the cartridge with itduring ramming.

The bottom part of the cartridge-guide comprises two guide bars 33,which are both supported on front and rear arms 34 pivotal about pivots35 between the positions illustrated in FIG. 4 in which they can.support a cartridge inserted into the cartridge-guide, and positions inwhich they are pivoted apart, so that a cartridge may be inserted intothe cartridge-guide from below by cartridge conveying means, which arenot illustrated in the drawing as not constituting part of theinvention.

Prior to ramming, the cartridge thus rests on the guide bare 33 in aposition to be brought to the cartridgechamber, which, in the samemanner as illustrated in FIGS. 1 to 3, is located in front of breechring 3. The internal surfaces 36 of guide bars 31 and 33 togetherconstitute the cartridge guiding surfaces of the device, said guidingsurfaces being located at a distance from each other corresponding tothe diameter of the bottomflange of a cartridge.

A guide member, which, as is described with reference to FIGS. 1 to 3,comprises guide lug 10' carried by arm 13, is arranged adjacent thefront end of each bar 33 and piovtal about pivot 12, each mounted on afront arm 34. In its normal front or forward position each guide memberis forced against abutment member 15 by means of spring 16 actuatinglever 17. Each one of said guide members is, as is also described abovewith reference to FIGS. 1

to 3, pivotal rearwardly when exposed to forces exerted thereon by acartridge-case ejected rearwardly after firing.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments thereof, it will be understood bythose skilled in the art, after understanding the invention, thatvarious changes and modifications may be made without departing from thespirit and scope of the invention, and it is intended, therefore, tocover all such changes and modifications in the appended claims.

What is claimed is:

1. A guide device for guiding a cartridge including a cartridge casinghaving a cylindrical portion with a bottom flange of -a diameter widerthan the cylindrical casing portion and a generally conical projectilefitted in the casing, while being rammed into the cartridge chamber of agun, said device comprising an elongated cartridge-guide means having aninner peripheral outline fitting the diameter of the bottom flange ofthe cartridge casing, said guide means being mounted in communicationwith and forming a continuation of the cartridge chamber in a positionin which the center axis of the guide means is in axial alignment withthe center axis of the cartridge chamber for guiding the cartridge fromthe guide means into the cartridge chamber, said cartridge while beingin the guide means having a downwardly slanted position in reference tothe center axis of the guide means, a guide member, mounting meanssupporting said guide member adjacent to the forward end of the guidemeans facing the cartridge chamber, pivotal about an axis transverse ofthe common center axis of the cartridge chamber and the guide means andlocated externally and below the bottom side of said guide means forpivoting said guide member lengthwise of said common center axis betweena forward position in which a portion of said guide member protrudesupwardly into said guide means to lift the projectile and thecylindrical portion of the cartridge while passing said protruding guidemember portion from said slanted position into a position substantiallycoaxial with the axis of the cartridge chamber and a rear position inwhich said portion of the guide member is withdrawn from said protrudingposition, and a directional force means biasing the guide member intosaid forward position, said guide member being pivotal toward its rearposition against the action of said force means when exposed to a forcein the rearward direction of the guide means.

2. A device according to claim 1, wherein said guide member in itsforward position extends into the cartridgeguide means a distancesubstantially equal to the difference between the maximum radius of thebottom flange of the casing of the cartridge and the radius of thecylindrical portion of the casing of said cartridge.

3. A device according to claim 1, wherein said cartridge-guide means isradially widened opposite said guide member to accommodate the bottomflange of a cartridge casing passing through the guide means.

4. A device according to claim 1, wherein said cartridge-guide meanscomprises several lengthwise parallel guide bars restricting lateralmovement of the cartridge in all lateral directions perpendicular to thelongitudinal axis thereof and defining a tubular member, and whereinsaid cartridge-guide means at a portion substantially diametricallyopposite to said guide member when the same is in its forward position,comprises a radially widened portion permitting passage of the bottomflange of the cartridge past said guide member portion in its forwardposition when the cartridge is guided into the cartridge chamber duringramming. 7

References Cited by the Examiner UNITED STATES PATENTS 2,907,251 10/1959 Sahlberg 89-47 FOREIGN PATENTS 117,523 2/ 1945 Australia.

BENJAMIN A. BORCHELT, Primary Examiner.

FRED C. MATTERN, 1a., Examiner.

S. C. BENTLEY, Assistant Examiner.

1. A GUIDE DEVICE FOR GUIDING A CARTRIDGE INCLUDING A CARTRIDGE CASINGHAVING A CYLINDRICAL PORTION WITH A BOTTOM FLANGE OF A DIAMETER WIDERTHAN THE CYLINDRICAL CASING PORTION AND A GENERALLY CONICAL PROJECTILEFITTED IN THE CASING, WHILE BEING RAMMED INTO THE CARTRIDGE CHAMBER OF AGUN, SAID DEVICE COMPRISING AN ELONGATED CARTRIDGE-GUIDE MEANS HAVING ANINNER PERIPHERAL OUTLINE FITTING THE DIAMETER OF THE BOTTOM FLNAGE OFTHE CARTRIDGE CASING, SAID GUIDE MEANS BEING MOUNTED IN COMMUNICATIONWITH AND FORMING A CONTINUATION OF THE CARTRIDGE CHAMBER IN A POSITIONIN WHICH THE CENTER AXIS OF THE GUIDE MEANS IS IN AXIAL ALIGNMENT WITHTHE CENTER AXIS OF THE CARTRIDGE CHAMBER FOR GUIDING THE CARTRIDGE FROMTHE GUIDE MEANS INTO THE CARTRIGDE CHAMBER, SAID CARTRIDGE WHILE BEINGIN THE GUIDE MEANS HAVING A DOWNWARDLY SLANTED POSITION IN REFERENCE TOTHE CENTER AXIS OF THE GUIDE MEANS, A GUIDE MEMBER, MOUNTING MEANSSUPPORTING SAID GUIDE MEMBER ADJACENT TO THE FORWARD END OF THE GUIDEMEANS FACING THE CARTRIDGE CHAMBER, PIVOTAL ABOUT AN AXIS TRANSVERSE OFTHE COMMON CENTER AXIS OF THE CARTRIDGE CHAMBER AND THE GUIDE MEANS ANDLOCATED MEANS TERNALLY AND BELOW THE BOTTOM SIDE OF SAID GUIDE MEAN FORPIVOTING SAID GUIDE MEMBER LENGTHWISE OF SAID MEANS MON CENTER AXISBETWEEN A FORWARD POSITION IN WHICH A PORTION OF SAID GUIDE MEMBERPROTRUDES UPWARDLY INTO SAID GUIDE MEANS TO LIFT THE PROJECTILE AND THECYLINDRICAL PORTION OF THE CARTRIDGE WHILE PASSING SAID PROTRUDING GUIDEMEMBER PORTION FROM SAID SLANTED POSITION INTO A POSITION SUBSTANTIALLYCOAXIAL WITH THE AXIS OF THE CARTRIDGE CHAMBER AND A REAR POSITION INWHICH SAID PORTION OF THE GUIDE MEMBER IS WITHDRAWN FROM SAID PROTRUDINGPOSITION, AND A DIRECTIONAL FORCE MEANS BIASING THE GUIDE MEMBER INTOSAID FORWARD POSITION, SAID GUIDE MEMBER BEING PIVOTAL TOWARD ITS REARPOSITION AGAINST THE ACTION OF SAID FORCE MEANS WHEN EXPOSED TO A FORCEIN THE REARWARD DIRECTION OF THE GUIDE MEANS.